Along with using dish detergent to wash your swim goggles, (you’ll never have foggy underwater vision again) being able to say “so what” is, indeed, one of the greatest tricks you can ever learn. For me, the coping mechanism of “so what” has manifested itself in a few different ways over the years.
A: “I don’t care.”
This sentiment is the most immature of the three. It forms on your tongue somewhere between the ages of seven and 14 when you realize that perhaps the best way to get back at someone is to simply act blasé. While this may be somewhat appropriate for middle school soap operatic situations, it is not the best choice of comebacks when life throws crap in your face later down the line.
Reason number one: Liar, you do care, you have crap on your face (figuratively, of course).
Reason number two: “I don’t care” is a statement meant more for the person hearing it than the person saying it. When life throws problems your way, “I don’t care” is just not going to cut it. Heads up, life is not a person. It’s really completely unbothered by your apparent lack of concern.
Moving right along to tactic B: “So what,”
la crème de la crème of coping mechanisms. “So what” is almost exactly like “I don’t care,” except it isn’t for anybody but yourself. You say it until you believe it, until whatever is bothering you just doesn’t matter anymore. Fake it ‘til you make it, baby. It’s magical.
Last, but certainly not least, C:  “________ doesn’t exist.” 
This one is my favorite. It goes a step beyond “So what.” “So what” turns your issues into non-issues. This statement proclaims your issues are not even there. Woo! That is my kind of party.
However, this sentiment can be a little tricky. You can potentially drive yourself nuts when you say, “My assignments don’t exist,” or “This person doesn’t exist,” and then the day your paper on “Songs of Innocence and Experience” is due you run into what’s-his-name at Piggly Wiggly.
So, use this statement responsibly, preferably on abstract issues such as your social anxiety or intellectual insecurities, and watch your confidence soar!
Hey, I totally recognize tactic C is bonkers and problematic, not to mention it potentially causes boatloads of inner turmoil. I still use it, but I use it sparingly, because as much as bad things are bad, they help you to see what is good, and I would never want to rob myself of that.
The lemons in life make the sweet part sweeter, right? And if there aren’t any sweet parts of life at present … so what.